EVALUATION OF B-LYMPHOCYTES AND T-LYMPHOCYTES AND PLASMA-CELLS IN COLONIC MUCOSA FROM HEALTHY DOGS AND FROM DOGS WITH INFLAMMATORY BOWEL-DISEASE

The aim of this study was to investigate the subpopulations of lymphoc ytes in the colonic mucosa of healthy dogs and dogs with inflammatory bowel disease (IBD). Fourteen normal dogs and 13 dogs with IBD were ex amined. Endoscopic biopsy specimens of colonic mucosa from each dog we re stained specifically for pan T lymphocytes (CD3) and pan B lymphocy tes (CD79a), and for plasma cells with methyl green pyronin (MGP) stai n. Cells were counted by means of a grid and statistical analysis was performed on the data collected. B and T lymphocytes were also counted in the glandular epithelium of normal dogs and dogs with IBD and the normal and abnormal groups compared statistically. Healthy dogs had si gnificantly lower numbers of T cells in the lamina propria and glandul ar epithelium and significantly lower numbers of B cells in the lamina propria. Significant group differences for plasma cells were not evid ent. Our results indicate that in IBD a chronic cellular immune reacti on is present in the diseased gut involving increased numbers of B and T lymphocytes.